Steps to repeat, eval the following and run `ert'.
(ert-deftest bad-equal ()
(should (equal 23 -50)))
Instead of a normal Ert error, the following is reported:
A bad-equal
aborted
When placing the cursor on the error and press "d" (to run the test case in the debugger), the following call stack is presented:
apply(debug (error (wrong-type-argument characterp -50)))
ert--run-test-debugger([cl-struct-ert--test-execution-info...
#[128 "\301\300\"\207" [[cl-struct-ert--test-execution-info ...
format("?%c" -50)
ert--explain-format-atom(-50)
ert--explain-equal-rec(23 -50)
ert--explain-equal(23 -50)
apply(ert--explain-equal (23 -50))
(list :explanation (apply -explainer- args-1))
Clearly, the code is trying to print -50 as a character.
This worked in Emacs 24.5, where Ert reported:
F bad-equal
(ert-test-failed
((should
(equal 23 -50))
:form
(equal 23 -50)
:value nil :explanation
(different-atoms
(23 "#x17" "?")
(-50 "#x3fffffffffffffce"))))
Sincerely,
Anders Lindgren
In GNU Emacs 25.0.50.158 (x86_64-apple-darwin14.5.0, NS appkit-1348.17 Version 10.10.5 (Build 14F27))
of 2015-10-16
Repository revision: ff4798b8b493ba1ec51dcb1c59a11824865124b8
Windowing system distributor 'Apple', version 10.3.1348
Configured using:
'configure --with-ns --without-dbus'
Configured features:
ACL ZLIB TOOLKIT_SCROLL_BARS NS
Important settings:
value of $LC_CTYPE: UTF-8
locale-coding-system: utf-8-unix
Major mode: ERT-Results
Minor modes in effect:
tooltip-mode: t
global-eldoc-mode: t
electric-indent-mode: t
mouse-wheel-mode: t
tool-bar-mode: t
menu-bar-mode: t
file-name-shadow-mode: t
global-font-lock-mode: t
font-lock-mode: t
blink-cursor-mode: t
auto-composition-mode: t
auto-encryption-mode: t
auto-compression-mode: t
buffer-read-only: t
line-number-mode: t
transient-mark-mode: t
Recent messages:
For information about GNU Emacs and the GNU system, type C-h C-a.
bad-equal
Ran 1 tests, 0 results were as expected, 1 unexpected
Running test bad-equal...
Entering debugger...
Load-path shadows:
None found.
Features:
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Memory information:
((conses 16 89635 5963)
(symbols 48 19436 0)
(miscs 40 78 159)
(strings 32 15385 4052)
(string-bytes 1 463936)
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(vector-slots 8 415700 5035)
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